nicolargo/glances · warning · HTTPException

Cannot get {item} unit for plugin {plugin} ({str(e)})

Error message

Cannot get {item} unit for plugin {plugin} ({str(e)})

What it means

Raised when get_item_info(item, 'unit') fails on the item-unit endpoint, returned as HTTP 404. Same metadata source as descriptions: the item must exist in the plugin's items description dict with a unit entry.

Source

Thrown at glances/outputs/glances_restful_api.py:1258

            )
        else:
            return GlancesJSONResponse(ret)

    def _api_item_unit(self, plugin: str, item: str):
        """Glances API RESTful implementation.

        Return the JSON representation of the couple plugin/item unit
        HTTP/200 if OK
        HTTP/400 if plugin is not found
        HTTP/404 if others error
        """
        self._check_if_plugin_available(plugin)

        try:
            # Get the unit
            ret = self.stats.get_plugin(plugin).get_item_info(item, 'unit')
        except Exception as e:
            raise HTTPException(status.HTTP_404_NOT_FOUND, f"Cannot get {item} unit for plugin {plugin} ({str(e)})")
        else:
            return GlancesJSONResponse(ret)

    def _api_value(self, plugin: str, item: str, value: str | int | float):
        """Glances API RESTful implementation.

        Return the process stats (dict) for the given item=value
        HTTP/200 if OK
        HTTP/400 if plugin is not found
        HTTP/404 if others error
        """
        self._check_if_plugin_available(plugin)

        # Update the stat
        self.__update_stats(get_plugin_dependencies(plugin))

        try:
            # Get the RAW value

View on GitHub (pinned to a240d8dfb3)

Solutions

1. Treat 404 as 'unitless' in client logic
2. Check known items via /api/4/<plugin>/views
3. Align with the deployed glances version's metadata

Example fix

# before
unit = fetch(f'/api/4/mem/{item}/unit').json()  # 404 for unitless items
# after
r = fetch(f'/api/4/mem/{item}/unit')
unit = r.json() if r.ok else ''

views = httpx.get(f'{BASE}/api/4/{plugin}/views').json()
has_unit = item in views

def has_unit(item: str, views: dict) -> bool:
    return item in views

r = httpx.get(f'{BASE}/api/4/{plugin}/{item}/unit')
unit = r.json() if r.status_code == 200 else ''  # unitless fallback

When it happens

Trigger: GET /api/4/<plugin>/<item>/unit for an item with no unit defined or not present in item metadata — e.g., counters or newly added fields.

Common situations: Clients auto-labeling units for every stat key; many items legitimately have no unit.

Related errors

• Cannot get {item} description for plugin {plugin} ({str(e)})
• Cannot get help view data ({str(e)})
• Cannot get plugin list ({str(e)})
• Cannot get stats ({str(e)})
• Cannot get limits ({str(e)})

AI-assisted analysis of nicolargo/glances@a240d8dfb3 (2026-08-27). Data as JSON: /api/errors/6fbb0199052e4dc9. Report an issue: GitHub.